Document: Signal Mountain Road Study

Crack in road on Signal Mountain

Crack in road on Signal Mountain

Photo by
Laura McNutt
/Times Free Press.

A cracked section of pavement on U.S. Highway 127 on Signal Mountain -- in the same area where the road fell off into the gorge in 2009 -- will be patched and monitored, according to the state Department of Transportation.

"Nothing is settling; everything is OK," TDOT spokeswoman Jennifer Flynn said last week after maintenance crews inspected the area near Palisades Drive that runs between a massive rock face and a sheer drop to the Tennessee River.

However, a new TDOT study says U.S. 127 between Suck Creek Road and Palisades Drive "has been experiencing a significant degradation for several years resulting in large rockslides, roadway failures and traffic delays" and "contains one of the 10 most hazardous rock fall sites in the state of Tennessee."

The cost of possible solutions ranges from about $5 million to more than $130 million.

Flynn described the new crack as about the width of a dime and 125 feet long. Motorists who have driven the road say the crack is in a slight trough in the pavement.

"They're going to put some crack sealant in there to keep water from getting in," Flynn said. "They do not consider it to be unsafe, plus the asphalt in that area is really, really, really thick. We don't consider it to be a safety problem but we'll continue to monitor it."

The crack follows months of above-average rainfall. January and December were both about 2 inches above normal.

Abnormally heavy rains were blamed when a long pavement section collapsed from U.S. 127 in December 2009. To fix it, repair crews dumped 18,000 tons of limestone into the hole at a cost of about $500,000, newspaper archives show.

At the time, the newspaper reported that the washout site was on a TDOT list of 36 trouble spots statewide.

Signal Mountain Mayor Bill Lusk said the state needs to find a long-term fix for water undermining the highway.

"TDOT has really worked to make sure that the road is safe. If there is an issue with the area that had collapsed previously, I'd be really surprised," Lusk said last week.

"I'm less concerned about the area that was repaired than I am about areas of the road that have not been repaired. The real issue is that there's essentially erosion under the road," he said.

The TDOT technical study, released in December, says the state must solve drainage and road instability problems.

One possible solution is making spot improvements to the existing road, such as new culverts, rock-fall mitigation and improved road stability. TDOT estimates that could cost from $5.5 million to $50 million.

Rebuilding the road in place with a new truck climbing lane is estimated to cost $75 million, according to the study. Building a new highway along what's now the W Road and Anderson Pike would cost more than $130 million, the study states.